Along with the development of electronic parts in recent years, there have been developed many kinds of display panels, such as plasma display panel, liquid-crystal display panel, electroluminescence panel, fluorescence display panel, electrochromic display panel, light-emitting diode display panel, and gas discharge type display panel. Of these, plasma display panel (hereinafter, abbreviated as PDP) attracts attention as a thin, large-size, flat plate type color display device. PDP has many cells between a front surface substrate, which is used as a display surface, and a back surface substrate. An image is formed by conducting plasma discharge in the cells. In this cell, a section is formed by a partition wall of an inorganic material. Electrodes are formed per each pixel in order to control the display condition in each pixel forming an image.
On this PDP's back surface substrate, partition walls for section formation of discharge cells are formed. In recent years, a demand for high precision has increased, and along therewith a demand for forming a partition wall layer with high aspect ratio and high precision has increased.
Furthermore, a high-price, high-strain point glass is used as a glass substrate in the production of PDP, since it is baked at a high temperature of around 600° C. There is, however, a desire from PDP makers to change it to a lower-price soda-lime glass. Thus, there is expected a development of a glass ceramic material for plasma display that can be baked at a low temperature of not higher than 560° C.
Hitherto, in the case of conducting patterning of inorganic material, sand blast method is frequently used. Sand blast method, however, has had a defect of no capability to form a partition wall layer with high aspect ratio and high precision, due to excessive grinding caused by rebound and electrification of grinding material, a phenomenon of so-called side etching.
Thus, there is proposed a manner of increasing grinding resistance by adding organic resin into glass paste (see Patent Publication 1).
Furthermore, there is proposed a method of forming a partition wall layer with high aspect ratio and high precision by photolithography technique using photosensitive glass paste (see Patent Publications 2-4).
Furthermore, there is proposed an example in which glass fine grains having a softening point of 800° C. have been added in about 20 weight % as a manner of widening the optimum baking temperature range (see Patent Publication 4).
Furthermore, in composition, there is proposed a system of using lead oxide and bismuth oxide for the purpose of improving thermal softening temperature and water resistance (see Patent Publications 2 and 4).    Patent Publication 1: Japanese Patent Application Publication 2003-257322    Patent Publication 2: Japanese Patent Publication 3402070    Patent Publication 3: Japanese Patent Publication 3696725    Patent Publication 4: Japanese Patent Publication 3716787